Panel-like structural members are commonly employed for the internal and external walls of dwellings, office buildings, warehouses and the like. Analogous construction is likewise used in certain vehicles such as tractor trailers, recreational vehicles, buses, airplanes and the like.
When such panels are permanently installed, there are occasions when a panel must be opened, preferably without removing and replacing the entire panel, in order to access wiring, plumbing fixture and the like which were disposed behind the panel in the course of the original construction. When such an extemporaneous access is necessary, an appropriate opening can be defined using a drill to create an access port and a scroll saw or the like to enter that part and carefully define the desired perimeter of the opening through which access to the previously hidden service problem is obtained.
Once the repair is effected, a clear need exists for means and methods to close that opening, preferably in a detachable and attractive fashion, to restore the integrity of the panel while permitting ready ingress and egress to the service facility for future repairs if needed. It is toward this end that the present invention is directed.
The prior art teaches three general types of plate-like closure means for panel openings. First, there is the sliding-type closure means exemplified by the double-hung window wherein the slidably closeable plate member remains within the plane of the panel opening. The main disadvantage of this type of closure arises from the inherently limited degree of ventilation obtainable which is usually limited to about 50 percent of the panel opening size. Second, there is the pivotal-type closure means wherein a single peripheral edge of the plate member is pivotably attached to the panel. The main disadvantage of the pivotal type of closure means is that the plate member projects excessively away from the panel in order to obtain full ventilation through the panel opening. Third, there is the scissors-type closure means wherein the entire periphery of the plate member is effectively attached to the periphery of the panel opening with a scissors-type linkage whereby the plate member is maintainable in substantial parallelism with the plane of the panel opening. The main disadvantages of the scissors-type closure means are the expense of the scissors-type linkage, the impediment it creates relative to air-flow characteristics, and the generally troublesome operational characteristics of scissors-type linkages per se.